Replace the VVT Phasers when replacing chains on a '16 LR4

Another question fpr everyone here that knows way more about these engines than me.
I'm going to be replacing the chains, guides, etc on my 2016 LR4 (~90k miles). My mechanic that I trust with my Benz, recommended that if we're going to do this job, we might as well replace the VVT Phasers as well.

One one hand, Id rather not because it's an extra ~$1000 in parts. But on the other hand... with how much I'm spending for everything else, I kinda feel it'd be kinda stupid to not do those as well and have to do the job again in the near-ish future. Since I dont know these engines well, I'm not sure how prone to issues those are. Is it common for them to get worn from the chains when the chains are going? I can imagine that with any amount of chain slap there's a potential for them to get a bit pitted from vibration/slap

I've seen comments in other forums that some guys with the 5.0 were doing them when they did their chains at 100K miles. I have the 3.0, but from what I understand its still basically the same motor and a lot of the stuff on the front side is (for the most part) the same.

Thoughts?

I opted not to do mine purely from a financial perspective; time will tell if it's an OK decision... I know with bike chains it's encouraged to swap out the cassette and front rings. I don't know how the stretching of the chain impacts the wear on the VVT's but I have to imagine that we're talking micromillimeters, probably it's not enough to do any harm and I suspect mechanically there's enough slop in the system to counter these small tolerances. My 2 cents!

When I was shopping for a mechanic to do my engine work, I came across a guy that wouldn't do the work because timing problems can still occur after doing the chain. The shop I went with wouldn't do the chains w/out replacing the timing actuators.

They turned out to be a shady shop, but I have no regrets putting in new actuators. In theory, if its true that long oil change durations cause the tensioner problems, then there could be problems with the actuators from bad oil too.

A few weeks later after the timing job was done, one of the oil pressure valves that controls the VVT devices went bad so I'd replace both of those while you are in there. There is one on each head and they are not expensive.

I’m in the process of doing the timing chains, tensioners, injectors, etc., along with a complete refresh of the entire cooling system including front and rear cross over pipes, water pump, thermostat, radiator, fan, and all of the coolant hoses.

I’ve debated replacing the VVTs, but haven’t ordered them yet. My plan is to put them through an ultrasonic cleaner and then inspect them and go from there. I’m going off of this video below to determine if I get mine replaced but so far it’s not part of the plan.


My LR4 is just over 144K miles and has been running solid. Passenger side chain has some slack in it but the driver side has no play.

-Christian

Longtrail said:

I opted not to do mine purely from a financial perspective; time will tell if it's an OK decision... I know with bike chains it's encouraged to swap out the cassette and front rings. I don't know how the stretching of the chain impacts the wear on the VVT's but I have to imagine that we're talking micromillimeters, probably it's not enough to do any harm and I suspect mechanically there's enough slop in the system to counter these small tolerances. My 2 cents!

Click to expand...

I guess I'm just paranoid having reading so many horror stories, and I'd rather not tempt fate and have to do the job again.

powershift said:

A few weeks later after the timing job was done, one of the oil pressure valves that controls the VVT devices went bad so I'd replace both of those while you are in there. There is one on each head and they are not expensive.

Click to expand...

Thanks for the tip, I'll add those to my list.

CPalacay said:

I’m in the process of doing the timing chains, tensioners, injectors, etc., along with a complete refresh of the entire cooling system including front and rear cross over pipes, water pump, thermostat, radiator, fan, and all of the coolant hoses.

I’ve debated replacing the VVTs, but haven’t ordered them yet. My plan is to put them through an ultrasonic cleaner and then inspect them and go from there. I’m going off of this video below to determine if I get mine replaced but so far it’s not part of the plan.

My LR4 is just over 144K miles and has been running solid. Passenger side chain has some slack in it but the driver side has no play.

-Christian

Click to expand...

Thanks for the video. I already know my shop wont want to rebuild them, and I have a feeling they're not going to want to wait for me to clean them out and return them and have my car occupy a bay in their garage until I get them cleaned and rebuilt. And if I'd rather just buy new ones than to pay for time to tear them all down and clean them.